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Store values loaded from the stat1 table as logarithmic values in memory.

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FossilOrigin-Name: 1bd74c49ddab6f53bb6eaa57907eff44c2580dd6
This commit is contained in:
dan
2014-04-25 15:01:01 +00:00
parent aa9933c115
commit cfc9df76e1
8 changed files with 72 additions and 51 deletions
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30
src/where.c
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@@ -1956,7 +1956,8 @@ static void whereKeyStats(
iLower = 0;
iUpper = aSample[0].anLt[iCol];
}else{
iUpper = i>=pIdx->nSample ? pIdx->aiRowEst[0] : aSample[i].anLt[iCol];
i64 nRow0 = sqlite3LogEstToInt(pIdx->aiRowLogEst[0]);
iUpper = i>=pIdx->nSample ? nRow0 : aSample[i].anLt[iCol];
iLower = aSample[i-1].anEq[iCol] + aSample[i-1].anLt[iCol];
}
aStat[1] = (pIdx->nKeyCol>iCol ? pIdx->aAvgEq[iCol] : 1);
@@ -2092,7 +2093,7 @@ static int whereRangeScanEst(
/* Determine iLower and iUpper using ($P) only. */
if( nEq==0 ){
iLower = 0;
iUpper = p->aiRowEst[0];
iUpper = sqlite3LogEstToInt(p->aiRowLogEst[0]);
}else{
/* Note: this call could be optimized away - since the same values must
** have been requested when testing key $P in whereEqualScanEst(). */
@@ -2251,6 +2252,7 @@ static int whereInScanEst(
tRowcnt *pnRow /* Write the revised row estimate here */
){
Index *p = pBuilder->pNew->u.btree.pIndex;
i64 nRow0 = sqlite3LogEstToInt(p->aiRowLogEst[0]);
int nRecValid = pBuilder->nRecValid;
int rc = SQLITE_OK; /* Subfunction return code */
tRowcnt nEst; /* Number of rows for a single term */
@@ -2259,14 +2261,14 @@ static int whereInScanEst(
assert( p->aSample!=0 );
for(i=0; rc==SQLITE_OK && i<pList->nExpr; i++){
nEst = p->aiRowEst[0];
nEst = nRow0;
rc = whereEqualScanEst(pParse, pBuilder, pList->a[i].pExpr, &nEst);
nRowEst += nEst;
pBuilder->nRecValid = nRecValid;
}
if( rc==SQLITE_OK ){
if( nRowEst > p->aiRowEst[0] ) nRowEst = p->aiRowEst[0];
if( nRowEst > nRow0 ) nRowEst = nRow0;
*pnRow = nRowEst;
WHERETRACE(0x10,("IN row estimate: est=%g\n", nRowEst));
}
@@ -4059,8 +4061,7 @@ static int whereLoopAddBtreeIndex(
assert( pNew->u.btree.nEq<=pProbe->nKeyCol );
if( pNew->u.btree.nEq < pProbe->nKeyCol ){
iCol = pProbe->aiColumn[pNew->u.btree.nEq];
nRowEst = sqlite3LogEst(pProbe->aiRowEst[pNew->u.btree.nEq+1]);
if( nRowEst==0 && pProbe->onError==OE_None ) nRowEst = 1;
nRowEst = pProbe->aiRowLogEst[pNew->u.btree.nEq+1];
}else{
iCol = -1;
nRowEst = 0;
@@ -4074,7 +4075,7 @@ static int whereLoopAddBtreeIndex(
saved_prereq = pNew->prereq;
saved_nOut = pNew->nOut;
pNew->rSetup = 0;
rLogSize = estLog(sqlite3LogEst(pProbe->aiRowEst[0]));
rLogSize = estLog(pProbe->aiRowLogEst[0]);
/* Consider using a skip-scan if there are no WHERE clause constraints
** available for the left-most terms of the index, and if the average
@@ -4082,10 +4083,11 @@ static int whereLoopAddBtreeIndex(
** number 18 was found by experimentation to be the payoff point where
** skip-scan become faster than a full-scan.
*/
assert( 42==sqlite3LogEst(18) );
if( pTerm==0
&& saved_nEq==saved_nSkip
&& saved_nEq+1<pProbe->nKeyCol
&& pProbe->aiRowEst[saved_nEq+1]>=18 /* TUNING: Minimum for skip-scan */
&& pProbe->aiRowLogEst[saved_nEq+1]>=42 /* TUNING: Minimum for skip-scan */
&& (rc = whereLoopResize(db, pNew, pNew->nLTerm+1))==SQLITE_OK
){
LogEst nIter;
@@ -4093,7 +4095,7 @@ static int whereLoopAddBtreeIndex(
pNew->u.btree.nSkip++;
pNew->aLTerm[pNew->nLTerm++] = 0;
pNew->wsFlags |= WHERE_SKIPSCAN;
nIter = sqlite3LogEst(pProbe->aiRowEst[0]/pProbe->aiRowEst[saved_nEq+1]);
nIter = pProbe->aiRowLogEst[0] - pProbe->aiRowLogEst[saved_nEq+1];
pNew->rRun = rLogSize + nIter;
pNew->nOut += nIter;
whereLoopAddBtreeIndex(pBuilder, pSrc, pProbe, nIter);
@@ -4305,7 +4307,7 @@ static int whereLoopAddBtree(
WhereInfo *pWInfo; /* WHERE analysis context */
Index *pProbe; /* An index we are evaluating */
Index sPk; /* A fake index object for the primary key */
tRowcnt aiRowEstPk[2]; /* The aiRowEst[] value for the sPk index */
LogEst aiRowEstPk[2]; /* The aiRowLogEst[] value for the sPk index */
i16 aiColumnPk = -1; /* The aColumn[] value for the sPk index */
SrcList *pTabList; /* The FROM clause */
struct SrcList_item *pSrc; /* The FROM clause btree term to add */
@@ -4340,12 +4342,12 @@ static int whereLoopAddBtree(
memset(&sPk, 0, sizeof(Index));
sPk.nKeyCol = 1;
sPk.aiColumn = &aiColumnPk;
sPk.aiRowEst = aiRowEstPk;
sPk.aiRowLogEst = aiRowEstPk;
sPk.onError = OE_Replace;
sPk.pTable = pTab;
sPk.szIdxRow = pTab->szTabRow;
aiRowEstPk[0] = pTab->nRowEst;
aiRowEstPk[1] = 1;
aiRowEstPk[0] = pTab->nRowLogEst;
aiRowEstPk[1] = 0;
pFirst = pSrc->pTab->pIndex;
if( pSrc->notIndexed==0 ){
/* The real indices of the table are only considered if the
@@ -4354,7 +4356,7 @@ static int whereLoopAddBtree(
}
pProbe = &sPk;
}
rSize = sqlite3LogEst(pTab->nRowEst);
rSize = pTab->nRowLogEst;
rLogSize = estLog(rSize);
#ifndef SQLITE_OMIT_AUTOMATIC_INDEX